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hostname of a machine interfered with static DNS record RRS feed

  • Question

  • I have an Active Directory network whose DCs are DNS and DHCP servers.

    Sometimes when a new computer joins the network, but not the active directory domain (in my case a Centos 7), it does a reverse lookup (part of dhcp I guess) and it renames the hostname accordingly. "Accordingly" means that if a previous computer, mobile phone or some other device used the ip that my virtual machine is currently using, then this new computer assumes its hostname. A little bit annoying, but that's that.

    Anyway, I obviously have some static associations, such as mail.domain.com 192.168.1.10. So what happened was that when I joined the network with my centos, whose hostname was mail.somestuff.com, the DNS record simply changed, based only on the "mail" prefix! That's how idiotically the microsoft DNS actually worked. So instead of having mail.domain.com 192.168.1.10, I got mail.domain.com 192.168.1.123 (the ip of my virtual machine).

    So it means that if I name the machine using an already used prefix, it might screw up the dns record, even if there's already a static record there! It doesn't make any sense.

    Can anyone explain to me what has happened and how I can avoid this in the future?

    Wednesday, May 31, 2017 9:12 AM

All replies

  • Hi lethargos

    I will test in my lab for a period of time.  If we have any updates or any thoughts about this issue, we will keep you posted as soon as possible.

    Best Regards,

    Candy


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    Thursday, June 1, 2017 7:53 AM
  • Just wanted to say that I tested it again with another hostname. This doesn't happen only with Centos, it happens with any operating system (I've tested it in Windows 10 too) and it doesn't matter if it belongs to AD or not.

    I created another static record testing.mydomain.com 192.168.1.10

    Then I started a new virtual machine which I've named testing.anotherdomain.com. The static record was, again, overwritten. So only the prefix actually matters, the dhcp/dns doesn't take into consideration the fqdn, it's only interested in the prefix.

    This is consistent, it doesn't happen once in a while. This is how the Windows DNS actually works.


    • Edited by lethargos Tuesday, June 6, 2017 11:55 AM
    Tuesday, June 6, 2017 11:50 AM
  • I've just tested it again in a lab environment and it doesn't overwrite the static records. I tried it both with Windows 7 and Centos. So I'm guessing the overwriting isn't actually normal behaviour. But I still don't understand why this is happening on the production servers. I've also tried using name protect, but to no avail. I'm guessing name protect actually is related exclusively to dhcp clients, and not to static records. I've no idea.
    Wednesday, June 7, 2017 2:18 PM
  • Hi lethargos,

    >>I tried it both with Windows 7 and Centos. So I'm guessing the overwriting isn't actually normal behaviour. 

    I have test in my lab and found it did not overwrite the static records.

    I suggest you could open a case with Microsoft, more in-depth investigation can be done so that you would get a more satisfying explanation and solution to this issue.

    Here is the link:

    https://support.microsoft.com/en-us/gp/support-options-for-business

    Best Regards,

    Candy


    Please remember to mark the replies as answers if they help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.

    Monday, June 12, 2017 10:09 AM
  • I'm really NOT going to buy support from Microsoft. We've already bought Windows licenses. You do have a sense of humour.
    Tuesday, June 13, 2017 11:23 AM